维生素C诱导了Tet-依赖的DNA脱甲基化和ES细胞中的囊胚状状态
Kathryn Blaschke1, Kevin T Ebata, Mohammad M Karimi
1Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Department of Obstetrics and Gynecology and Center for Reproductive Sciences, University of California San Francisco, San Francisco, California 94143, USA.
Nature
|July 2, 2013
概括
维生素C直接增强十一转位 (Tet) 酶活性,增加5-基甲基细胞素 (5hmC) 水平,促进小鼠胚胎干细胞中的DNA脱甲基化,从而保持表观遗传忠实.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 分子生物学分子生物学
- 基因组学就是基因组学.
背景情况:
- 基因甲基化是一种关键的表观遗传标记,调节基因表达,印记和逆转移素沉默.
- 十个十一转位 (Tet) 酶通过将5-甲基细胞因子 (5mC) 转化为5-基甲基细胞因子 (5hmC) 来调解DNA脱甲基化.
- 鼠标胚胎干细胞 (ESC) 通常在没有维生素C的情况下培养,这是Tet酶的潜在辅因子.
研究的目的:
- 研究维生素C在调节Tet酶活性和小鼠ESC中的DNA甲基化中的作用.
- 确定维生素C是否影响ESC的全球DNA脱甲基化和基因表达.
主要方法:
- 将维生素C添加到培养小鼠ESC中.
- 测量5hmC和5-甲基细胞素 (5mC) 的水平.
- 对基因促进物甲基化和基因表达的分析.
- 生物化学测定与重组Tet1.1. 的测定.
- 使用Tet1和Tet2双击ESC的实验.
主要成果:
- 维生素C在ESC中迅速且在全球范围内增加了5hmC水平.
- 其次是基因促进者的DNA脱甲基化和生殖基因的上调调节.
- 维生素C在体外和体内增强了Tet1活性,特别是在依赖Tet1/Tet2的区域.
- 与胚胎囊相比,维生素C对培养ESC的甲基化增长的影响更为明显.
结论:
- 维生素C作为TET酶活性的直接调节剂.
- 维生素C对于维持ESC中DNA甲基化忠实度至关重要.
- 维生素C在早期发育过程中影响表观遗传重编程.
相关概念视频
Maintenance of the ES Cell State
The cells of the blastocyst inner cell mass only remain pluripotent for a short time. This state of pluripotency and self-renewal can be maintained in embryonic stem (ES) cell culture by adding specific chemicals or growth factors to ensure the cells can continue dividing and later differentiate into different cell types. In some cases, the cells are grown on a feeder layer of differentiated cells, which provides the growth factors and extracellular matrix components necessary for stem cell...
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Embryonic stem (ES) cells were first discovered in mice in 1981 by Martin Evans. In 1998, James Thomson identified a method to isolate embryonic stem cells from humans. Human embryonic stem cells (hESCs) are obtained from 3-5 day old embryos that remain unused after an in vitro fertilization procedure.
ES cells are grown in a culture medium where they can divide indefinitely, creating ES cell lines. Under certain conditions, ES cells can differentiate, either spontaneously into a variety of...
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The development of all multicellular organisms starts with the fusion of haploid cells called sperm and egg to form a diploid zygote. A zygote is a totipotent cell that can develop into a complete organism. The zygote undergoes cell division or cleavage to form an 8-cell mass. Until this stage, the cells are spherical, loosely attached, and remain totipotent. Totipotent cells are capable of developing both the embryonic and the extraembryonic tissues. However, as they continue to divide, they...
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Nuclear reprogramming is a process of transforming one cell type into an unrelated cell type by epigenetic changes that alter the cell’s original gene expression pattern. Such epigenetic changes force cells to express a different set of genes, which play a significant role in inducing transformation into other cell types. Nuclear reprogramming offers applications in reproductive cloning for livestock propagation and regenerative medicine — developing patient-specific cells for injury repair.


